A232710 Binary numbers (written in decimal) such that the sum of digits mod 2 equals the product of digits mod 2.

0, 1, 5, 6, 7, 9, 10, 12, 17, 18, 20, 23, 24, 27, 29, 30, 31, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58, 60, 65, 66, 68, 71, 72, 75, 77, 78, 80, 83, 85, 86, 89, 90, 92, 95, 96, 99, 101, 102, 105, 106, 108, 111, 113, 114, 116, 119, 120, 123, 125

Offset: 0

Author

Jon Perry, Nov 28 2013

Keywords

• nonn
• base

Examples

			23 is in the sequence because 23 in binary is 10111. The sum of digits is 4 == 0 mod 2 and the products of digits is 0 == 0 mod 2.
		

Links

• Index entries for sequences related to binary expansion of n

Programs

JavaScript

for (i=0;i<1000;i++) {
s=i.toString(2).split("");
sl=s.length;
c=0;d=1;
for (j=0;j
				

PARI

is(n)=b=binary(n);sum(i=1,#b,b[i])%2==prod(i=1,#b,b[i])%2 \\ Ralf Stephan, Nov 30 2013

Formula

A083420 UNION (A001969 \ {3}). - Ralf Stephan, Nov 30 2013